adc Calculation

RE: adc Calculation

Jørgen Holmefjord — Thu, 19 Dec 2019 09:16:40 GMT

ADC_SCALING is determined by the SAADC GAIN configuration.

If you use printf() to print data to UART, you can use the float directly as a parameter to "%f" format string.

RE: adc Calculation

Sundar_santhanam@1998 — Wed, 18 Dec 2019 18:35:34 GMT

And also after obtaining the Voltage how do I display that float value in UART?

RE: adc Calculation

Sundar_santhanam@1998 — Wed, 18 Dec 2019 18:12:08 GMT

Hi what is meant by

ADC_SCALING ?

I am using (nRF52840)IR sharp sensor to calculate voltage from adc values.
Please tell me the formula to use if possible. I am using default saadc example code.

RE: adc Calculation

Jørgen Holmefjord — Mon, 12 Jun 2017 08:41:35 GMT

Hi,

You should be able to use this formula when calculating the voltage from ADC result.

V = (((ADC_VALUE * ADC_REF_VOLTAGE) / (2^(ADC_RESOLUTION)-1)) / ADC_SCALING) V

For your settings this will give:

V = (((ADC_VALUE * 1.2) / (1023)) / (1/3)) V

V = (((ADC_VALUE * 1.2) / (1023)) * 3) V

Best regards,

Jørgen